Automatic block-signaling system.



PATENTED OCT. 1 1907.

v D. J. MGOARTHY- AUTOMATIC BLOCK SIGNALING SYSTEM;

APPLICATION FILED AUG. 16, 1907.

WITNESSES UNITED STAlliBAEENT OFFICE,"

DANIEL J. MCCARTHY, OF WILKINSBURG, PENNSYLVANIA, ASSIGNOR TO THE UNION SWITCH & SIGNAL COMPANY, OF SWISSVALE, PENNSYLVANIA, A CORPORATION OF PENNSYL- VANI A.

v No. 867,563.

that character in which the distant signals are operated by the track. circuit without the use of separate wires or conductors thereiorfcontrol being effected by reversing the polarity of the track circuit by a pole changer operated by the home signal, both home and distant signals being controlled from a polarized track relay. The contacts on this relay are so arranged that either the operating circuit for the home signal alone or the circuits for both the home and distant signals can be closed, depending upon the polarity of the track circuit. When the home signal is clear, the shifting of the contacts to clear the distant signal causes a momentary break in the circuit to the home signal, and where electric signals using slots. are employed, it is necessary to so design these slots that they will not release during this momentary pauseof current, since such release wouldcause the home signal to move to danger position In direct current systems of this character, this is accomplished by placing a copper tube over the cores of the slot magnets, so that when the current in' the slot coils is interrupted a current will be induced in these tubes, thereby causinga magnetic flux in the cores of the slot magnets to hold their armature down during the momentary pause of current in the slot coils, and giving said coils a slow release. .When alternating current signals are employed, however, with alternating current slot magnets, these copper tubes cannot be used on the cores of the slot magnets, and it is necessary to provide some other means to'give these magnets a slow release so that they can be adapted to the polarized track system. The object of my invention is to provide means of this character, whereby alternating current slot magnets can be used in a system of wireless control for distant signals similar to those now in use in direct current systems having direct current slot magnets; and my inventioii consists in the provision of an auxiliary circuit-controlling device which. will hold the circuit of the slot magnet for the home signal closed during the time the main relay is moving from one of its operative positions to the other. The precise nature of my inventidnflwill be best understood by reference to the. accompanying drawings, which will now be described, it being premised, however, that the various parts are there shown diaoperative positions. tions it connects the contacts 13, and in the other po- AUTOMATIG BLOCK-SIGNALING SYSTEM.

Specification of Letters Patent.

Application filedAugust 16,1907. Serial No. 388,750-

Patented Oct. 1, 1907.

grammatically and that the invention is susceptible of various modifications and embodiments.

In this drawing, the numeral 2 designates the track rails, which are divided by insulated joints 3 into blocks or sections A and B.

4 designates apair of. line wires, which are supplied by an alternating current generator 5.

6 is a three-position alternating current relay, whose itEfiSITHD armature'windings 7 are shown as connected across the rails 2 of the block or section A, and whose field windings 8 are connected across the line wires 4. If desired,

across 'the line wires, the secondary coil being 'connected to the rails through a pole changer 9 operated by a.connection with the home signal blade H for the block or section B.

D is the distant signal blade for the block'B;- H the home signal blade for the block A, and is the distant signal blade for the block A. a

10 and 11 designate the respectivcslot-magnets for the home and distant signalblades H and D.' These two blades are operated by the one motor 12, the slot magnets 10 and 11 constituting the selective means of well-known character by which the respective blades can bebleared independently of each other.

The relay 7 has a central neutral position, andtwo In one of these operative posi- .cuit and in series with one of the contacts 15.

18 designates an auxiliary relay, having an actuating coil 19 connected across the line wires through the contacts 13 or 14, according to the position of the main relay. The rotor member of this auxiliary relay actuates a circuit closer 20, which, when the relay is in the position shown, closes the contacts 21 to completethe circuit of the slot magnet 10 through conductors 22 and 23 connected to the respective line wires. This breaker is of slow-acting type, this beingindicated in the diagram by showing that a considerable movement oi the rotor member will take place before the circuit break r will move to its open position.

When the block A is occupied by. train, the armature winding of the relay 6 is short circuited, and this relay is in its neutral position. This opens the contact's13, 14 and 15 and all the local circuits to the home signal H and distant signal D, causing these signals to "indicate-a danger condition. When the train passes auxiliary slow-releasing relay 18 which closes the coni I I0 and 11 to be energized. As the signal H clears, the

it This prevents the signal H from tacts-Zl and thereby causes the coils of the slot magnets circuit of the motor 12 broken at 16, and the signal H is held at clear position by the slot magnet 10, it being energized from the line wires 4 through the contacts 21.

When the train passes out of the block B, the home signal H is cleared. In clearing it operates the pole changer 9, which reverses the polarity of the track circuit in the block A, causing. the armature of relay 6 to reverse its direction of rotation. This breaks the circuit at the contacts 18 and closes the circuits at the contacts 14 and 15, thereby closing the local circuit to the motor 12 and the slot magnet 11, which causes the clearing of the distant signal D. As this signal clears 25 the circuit'of the motor 12 is broken at the contact 17.

It will be noted that as the armature of the relay 6 I The movable member of this relay, however, has to make a considerable movement before the contacts at 21 areopened, the duration of this movement being sufiicient to prevent the slot magnet 10 from being deenergized during the movement of the main relay.

going to danger position, while the relay 6 is reversing.

By the provision of a simple form of slow-releasing .relayvforlmaintaining the circuit of the slot magnets 3 during the reversal of the main relay, I am enabled to use alternating current slot magnets in a system of wireless-control for distant signals in a similar manner to the direct current system now in use.

It will be undersood that various forms of the auiziliary relay 18 may be employed for this purpose.

What I claim is 1. In an alternating current block signaling system. :i normally closed track circuit, line wires from which the track circuit is energized, means for reversing the polnn ity of the track circuit, a reversing relay controlled by the reversal of polarity of the track circuit and controlling the operating mechanism for the home and distant signal blades. alternating current slot magnets. and an auxiliary circuit controlling device for holding" the cirsuit of the home signal slotmagnct closed while the relay is reversing; substantially as described.

2. In alternating current block signaling system of the character described, a main reversing relay, :1 slot mn;:- net for the home signal aud an auxiliary circuit-controlling device for maintaining the circuit of the slot mugnet closed while the relay is reversing; substantially as described. 1

3. In an automatic block signaling system using aircrnating current, a closed truck circuit, :1 reversing relay controlled thereby, home and distant signal blades, on actuating motor therefor. alternating current slot mug nets. an auxiliary circuit-closing device for holding the circuit of the home signal slot magnets closed while the relay is reversing; substantially as described.

4. In an alternating current block signaling system of the character described, a slot magnet, a reversing relay, and an auxiliary device for maintaining the clrcult of. the slot magnet while the relay is reversing; substantially as described.

In an alternating current block signaling system of the character described, an alternating current slot mu:- net, a reversing relay, and an auxiliary device controlled by the track circuit for maintaining the circuit of the slot magnet while the relay is reversing; substantially as described.

6. In an alternating current block-signaling system of the character described, home and distant signal blades. a reversing relay through which said blades are controlled by the track circuits, a line circuit, and an alternating current slot magnet, and a slowmotiou circuit controlling device for controlling the circuit of said magnet; substan tially as described.

In testimony whereof, I hhvehcreunto set my hand.

DANIEL J. MCCARTHY.

Witnesses:

L. Fnsnnnic How/mo, JOHN D. TAYLOR. 

